feat: undo a delete to Trash, archive, move, spam report or remove from folder from its toast

components/email/__tests__/permanent-delete-feedback.test.tsx

@@ -62,8 +62,9 @@ async function clickDelete(surface: string) {
     fireEvent.contextMenu(await screen.findByText('ok')); fireEvent.click(await screen.findByTestId('ctx-delete'));
   } else {
     fireEvent.click(surface === 'mountain' ? screen.getByLabelText('delete') : screen.getByTitle('batch_actions.delete'));
-    fireEvent.click(within(await screen.findByRole('alertdialog')).getByRole('button', { name: 'permanent_delete' }));
   }
+  // A permanent delete asks first, from every place it is offered.
+  fireEvent.click(within(await screen.findByRole('alertdialog')).getByRole('button', { name: 'permanent_delete' }));
 }
 
 for (const surface of ['mountain', 'default', 'context']) describe(surface + ' permanent bulk-delete feedback', () => {

components/email/email-list.tsx

@@ -15,7 +15,7 @@ import { Trash2, Mail, MailX, MailOpen, Loader2, SearchX, AlertTriangle, Calenda
 import { useState, useEffect, useLayoutEffect, useRef, useCallback, useMemo } from "react";
 import { Button } from "@/components/ui/button";
 import { ConfirmDialog } from "@/components/ui/confirm-dialog";
-import { useEmailStore, ArchiveMailboxNotFoundError, resolveSelectedEmails, bulkDeleteIsPermanent, shouldConfirmBulkDelete, removalFolder, canRemoveFromFolder, type ListRow } from "@/stores/email-store";
+import { useEmailStore, ArchiveMailboxNotFoundError, resolveSelectedEmails, bulkDeleteIsPermanent, shouldConfirmBulkDelete, removalFolder, canRemoveFromFolder, restoreBatchesForSelection, isAggregateListView, type ListRow } from "@/stores/email-store";
 import { useRemoveFromFolder } from "@/hooks/use-remove-from-folder";
 import { useShallow } from "zustand/react/shallow";
 import { useAuthStore } from "@/stores/auth-store";
@@ -29,7 +29,7 @@ import { useContextMenu } from "@/hooks/use-context-menu";
 import { useConfirmDialog } from "@/hooks/use-confirm-dialog";
 import { useTranslations } from "next-intl";
 import { toast } from "@/stores/toast-store";
-import { runBatchEmailAction } from "@/lib/email-action-toast";
+import { runBatchEmailAction, toastWithUndo, undoLabels, undoMoveAction } from "@/lib/email-action-toast";
 import { useVirtualizer } from "@tanstack/react-virtual";
 import { TagDisplayContext, useMeasuredTagDisplay } from "@/hooks/use-tag-display";
 import { SearchChips } from "@/components/search/search-chips";
@@ -168,6 +168,7 @@ export function EmailList({
   const tSpam = useTranslations('email_viewer.spam');
   const tNotifications = useTranslations('notifications');
   const tViewer = useTranslations('email_viewer');
+  const undo = undoLabels(tNotifications);
   const { client } = useAuthStore(useShallow((state) => ({ client: state.client })));
   const {
     selectedEmailKeys,
@@ -605,7 +606,10 @@ export function EmailList({
     setIsProcessing(true);
     try {
       const emailIds = resolveSelectedEmails(useEmailStore.getState()).map(e => e.id);
-      if (await batchUndoSpam(client, emailIds)) toast.success(tSpam('toast_not_spam_batch', { count: emailIds.length }));
+      const restore = restoreBatchesForSelection(client);
+      if (await batchUndoSpam(client, emailIds)) {
+        toastWithUndo(tSpam('toast_not_spam_batch', { count: emailIds.length }), undoMoveAction(client, restore, undo));
+      }
     } catch {
       toast.error(tSpam('error_not_spam'));
     } finally {
@@ -613,6 +617,63 @@ export function EmailList({
     }
   };
 
+  const handleBatchMarkAsSpam = async () => {
+    if (!client || isProcessing) return;
+    setIsProcessing(true);
+    try {
+      const emailIds = resolveSelectedEmails(useEmailStore.getState()).map(e => e.id);
+      const restore = restoreBatchesForSelection(client);
+      if (await batchMarkAsSpam(client, emailIds)) {
+        toastWithUndo(tSpam('toast_batch', { count: emailIds.length }), undoMoveAction(client, restore, undo));
+      }
+    } catch {
+      toast.error(tSpam('error'));
+    } finally {
+      setTimeout(() => setIsProcessing(false), 500);
+    }
+  };
+
+  const handleBatchArchive = async () => {
+    if (!client || isProcessing) return;
+    setIsProcessing(true);
+    const count = selectedEmailKeys.size;
+    const restore = restoreBatchesForSelection(client);
+    try {
+      await runBatchEmailAction(() => batchArchive(client), {
+        success: tNotifications('emails_archived', { count }),
+        error: tNotifications('error_archiving'),
+        describeError: (error) => error instanceof ArchiveMailboxNotFoundError
+          ? tViewer('archive_mailbox_not_found')
+          : undefined,
+        undo: undoMoveAction(client, restore, undo),
+      });
+    } finally {
+      setTimeout(() => setIsProcessing(false), 500);
+    }
+  };
+
+  const handleBatchMoveToMailbox = async (mailboxId: string) => {
+    if (!client || isProcessing) return;
+    setIsProcessing(true);
+    const count = selectedEmailKeys.size;
+    // A move to another account's folder copies the messages there, which
+    // Undo can't take back.
+    const destination = mailboxes.find(m => m.id === mailboxId);
+    const source = mailboxes.find(m => m.id === selectedMailbox);
+    const crossAccount = isAggregateListView()
+      || (!!destination?.accountId && !!source?.accountId && destination.accountId !== source.accountId);
+    const restore = crossAccount ? null : restoreBatchesForSelection(client);
+    try {
+      await runBatchEmailAction(() => batchMoveToMailbox(client, mailboxId), {
+        success: tNotifications('emails_moved', { count }),
+        error: tNotifications('move_failed'),
+        undo: undoMoveAction(client, restore, undo),
+      });
+    } finally {
+      setTimeout(() => setIsProcessing(false), 500);
+    }
+  };
+
   const handleBatchDelete = async () => {
     if (!client || isProcessing) return;
 
@@ -637,10 +698,12 @@ export function EmailList({
 
     setIsProcessing(true);
     const count = selectedEmailKeys.size;
+    const restore = isInTrash ? null : restoreBatchesForSelection(client);
     try {
       await runBatchEmailAction(() => batchDelete(client, isInTrash), {
         success: tNotifications('emails_deleted', { count }),
         error: tNotifications('error_deleting'),
+        undo: undoMoveAction(client, restore, undo),
       });
     } finally {
       setTimeout(() => setIsProcessing(false), 500);
@@ -1171,57 +1234,15 @@ export function EmailList({
           batchTagIds={selectionTags.all}
           batchPartialTagIds={selectionTags.some}
           onBatchToggleTag={handleBatchToggleTag}
-          onBatchDelete={async () => {
-            if (!client) return;
-            const count = selectedEmailKeys.size;
-            await runBatchEmailAction(() => batchDelete(client), {
-              success: tNotifications('emails_deleted', { count }),
-              error: tNotifications('error_deleting'),
-            });
-          }}
-          onBatchArchive={async () => {
-            if (!client) return;
-            const count = selectedEmailKeys.size;
-            await runBatchEmailAction(() => batchArchive(client), {
-              success: tNotifications('emails_archived', { count }),
-              error: tNotifications('error_archiving'),
-              describeError: (error) => error instanceof ArchiveMailboxNotFoundError
-                ? tViewer('archive_mailbox_not_found')
-                : undefined,
-            });
-          }}
+          onBatchDelete={() => void handleBatchDelete()}
+          onBatchArchive={() => void handleBatchArchive()}
           batchEmails={selectedEmailsForRemoval}
           onBatchRemoveFromFolder={() => void handleBatchRemoveFromFolder()}
-          onBatchMoveToMailbox={async (mailboxId) => {
-            if (!client) return;
-            const count = selectedEmailKeys.size;
-            await runBatchEmailAction(() => batchMoveToMailbox(client, mailboxId), {
-              success: tNotifications('emails_moved', { count }),
-              error: tNotifications('move_failed'),
-            });
-          }}
-          onBatchMarkAsSpam={async () => {
-            if (client) {
-              const emailIds = resolveSelectedEmails(useEmailStore.getState()).map(e => e.id);
-              try {
-                if (await batchMarkAsSpam(client, emailIds)) toast.success(
-                  tSpam('toast_batch', { count: emailIds.length })
-                );
-              } catch {
-                toast.error(tSpam('error'));
-              }
-            }
-          }}
+          onBatchMoveToMailbox={(mailboxId) => void handleBatchMoveToMailbox(mailboxId)}
+          onBatchMarkAsSpam={() => void handleBatchMarkAsSpam()}
           onBatchUndoSpam={async () => {
             if (client) {
-              const emailIds = resolveSelectedEmails(useEmailStore.getState()).map(e => e.id);
-              try {
-                if (await batchUndoSpam(client, emailIds)) toast.success(
-                  tSpam('toast_not_spam_batch', { count: emailIds.length })
-                );
-              } catch {
-                toast.error(tSpam('error_not_spam'));
-              }
+              await handleBatchUndoSpam();
             }
           }}
         />

components/email/mv-list-toolbar.tsx

@@ -22,9 +22,9 @@ import {
 import { useTranslations } from "next-intl";
 import { useAuthStore } from "@/stores/auth-store";
 import { useShallow } from "zustand/react/shallow";
-import { useEmailStore, ArchiveMailboxNotFoundError, resolveSelectedEmails, bulkDeleteIsPermanent, shouldConfirmBulkDelete, removalFolder, canRemoveFromFolder } from "@/stores/email-store";
+import { useEmailStore, ArchiveMailboxNotFoundError, resolveSelectedEmails, bulkDeleteIsPermanent, shouldConfirmBulkDelete, removalFolder, canRemoveFromFolder, restoreBatchesForSelection } from "@/stores/email-store";
 import { useRemoveFromFolder } from "@/hooks/use-remove-from-folder";
-import { runBatchEmailAction } from "@/lib/email-action-toast";
+import { runBatchEmailAction, toastWithUndo, undoLabels, undoMoveAction } from "@/lib/email-action-toast";
 import { toast } from "@/stores/toast-store";
 import { useConfirmDialog } from "@/hooks/use-confirm-dialog";
 import { useMenuNavigation } from "@/hooks/use-menu-navigation";
@@ -117,6 +117,7 @@ export function MvListToolbar({
   const tViewer = useTranslations("email_viewer");
   const tNotifications = useTranslations("notifications");
   const tSpam = useTranslations("email_viewer.spam");
+  const undo = undoLabels(tNotifications);
 
   const client = useAuthStore((s) => s.client);
   const {
@@ -232,7 +233,7 @@ export function MvListToolbar({
   // rejected promise or a store error turns into an error toast instead of
   // an unhandled rejection with nothing on screen.
   const run = async (
-    action: () => Promise<void>,
+    action: () => Promise<boolean | void>,
     messages?: Parameters<typeof runBatchEmailAction>[1],
   ) => {
     if (!client || isProcessing) return;
@@ -279,9 +280,11 @@ export function MvListToolbar({
         });
         if (!confirmed) return;
       }
-      await runBatchEmailAction(() => batchDelete(client, isInTrash), {
+      const restore = permanent ? null : restoreBatchesForSelection(client);
+      await runBatchEmailAction(() => batchDelete(client, permanent), {
         success: tNotifications("emails_deleted", { count: selectionCount }),
         error: tNotifications("error_deleting"),
+        undo: undoMoveAction(client, restore, undo),
       });
     });
 
@@ -360,11 +363,11 @@ export function MvListToolbar({
   const handleMove = (mailboxId: string) => {
     setMoveOpen(false);
     const count = selectionCount;
-    void run(async () => {
-      if (client) await batchMoveToMailbox(client, mailboxId);
-    }, {
+    const restore = client ? restoreBatchesForSelection(client) : null;
+    void run(async () => (client ? batchMoveToMailbox(client, mailboxId) : false), {
       success: tNotifications("emails_moved", { count }),
       error: tNotifications("move_failed"),
+      undo: undoMoveAction(client, restore, undo),
     });
   };
 
@@ -381,11 +384,12 @@ export function MvListToolbar({
     run(async () => {
       if (!client) return;
       const ids = resolveSelectedEmails(useEmailStore.getState()).map((email) => email.id);
+      const restore = restoreBatchesForSelection(client);
       try {
         if (isInJunk) {
-          if (await batchUndoSpam(client, ids)) toast.success(tSpam("toast_not_spam_batch", { count: ids.length }));
+          if (await batchUndoSpam(client, ids)) toastWithUndo(tSpam("toast_not_spam_batch", { count: ids.length }), undoMoveAction(client, restore, undo));
         } else {
-          if (await batchMarkAsSpam(client, ids)) toast.success(tSpam("toast_batch", { count: ids.length }));
+          if (await batchMarkAsSpam(client, ids)) toastWithUndo(tSpam("toast_batch", { count: ids.length }), undoMoveAction(client, restore, undo));
         }
       } catch {
         toast.error(isInJunk ? tSpam("error_not_spam") : tSpam("error"));
@@ -508,12 +512,13 @@ export function MvListToolbar({
             <ToolbarButton
               icon={Archive}
               label={tActions("archive")}
-              onClick={() => run(async () => { if (client) await batchArchive(client); }, {
+              onClick={() => run(async () => (client ? batchArchive(client) : false), {
                 success: tNotifications("emails_archived", { count: selectionCount }),
                 error: tNotifications("error_archiving"),
                 describeError: (error) => error instanceof ArchiveMailboxNotFoundError
                   ? tViewer("archive_mailbox_not_found")
                   : undefined,
+                undo: undoMoveAction(client, client ? restoreBatchesForSelection(client) : null, undo),
               })}
               disabled={isProcessing}
               busy={isProcessing}

components/layout/sidebar.tsx

@@ -72,6 +72,7 @@ import { useSettingsStore, getKeywordVisibility } from "@/stores/settings-store"
 import { usePolicyStore } from "@/stores/policy-store";
 import { useEmailStore } from "@/stores/email-store";
 import { toast } from "@/stores/toast-store";
+import { toastWithUndo, undoLabels, undoMoveAction } from "@/lib/email-action-toast";
 import { debug } from "@/lib/debug";
 import { AccountSwitcher } from "./account-switcher";
 import { useIsEmbedded } from "@/hooks/use-is-embedded";
@@ -634,18 +635,12 @@ function MailboxTreeItem({
   const { dropHandlers, isValidDropTarget, isInvalidDropTarget } = useMailboxDrop({
     mailbox: node,
     accountId: dragAccountId ?? undefined,
-    onSuccess: (count, mailboxName) => {
-      if (count === 1) {
-        toast.success(
-          tNotifications('email_moved'),
-          tNotifications('moved_to_mailbox', { mailbox: mailboxName })
-        );
-      } else {
-        toast.success(
-          tNotifications('emails_moved', { count }),
-          tNotifications('moved_to_mailbox', { mailbox: mailboxName })
-        );
-      }
+    onSuccess: (count, mailboxName, restore) => {
+      toastWithUndo(
+        count === 1 ? tNotifications('email_moved') : tNotifications('emails_moved', { count }),
+        undoMoveAction(useAuthStore.getState().client, restore, undoLabels(tNotifications)),
+        tNotifications('moved_to_mailbox', { mailbox: mailboxName }),
+      );
     },
     onError: () => {
       toast.error(tNotifications('move_failed'), tNotifications('move_error'));

components/mail/__tests__/mail-app-delete-action.test.tsx

@@ -136,3 +136,27 @@ describe('Delete on a selection', () => {
     expect(bulkDeleteIsPermanent({ role: 'inbox' })).toBe(false);
   });
 });
+
+describe('Undo after a delete to Trash', () => {
+  it('puts the message back where it was, unread again', async () => {
+    useSettingsStore.setState({ deleteAction: 'trash-and-read' } as never);
+    client.restoreEmails = vi.fn().mockResolvedValue(undefined);
+    render(<MailApp />);
+    fireEvent.click(await screen.findByText('stub delete', {}, { timeout: 5000 }));
+    await waitFor(() => expect(useToastStore.getState().toasts.some(t => t.title === 'notifications.email_deleted')).toBe(true));
+    const deleted = useToastStore.getState().toasts.find(t => t.title === 'notifications.email_deleted')!;
+    expect(deleted.action?.label).toBe('undo');
+    deleted.action!.onClick();
+    await waitFor(() => expect(client.restoreEmails).toHaveBeenCalled());
+    expect(client.restoreEmails).toHaveBeenCalledWith([{ id: 'm1', mailboxIds: { inbox: true }, seen: false }], undefined);
+  });
+
+  it('is not offered for a permanent delete', async () => {
+    useSettingsStore.setState({ deleteAction: 'permanent' } as never);
+    render(<MailApp />);
+    fireEvent.click(await screen.findByText('stub delete', {}, { timeout: 5000 }));
+    fireEvent.click(await screen.findByText('email_list.permanent_delete', { selector: 'button' }));
+    await waitFor(() => expect(useToastStore.getState().toasts.some(t => t.title === 'notifications.email_deleted')).toBe(true));
+    expect(useToastStore.getState().toasts.find(t => t.title === 'notifications.email_deleted')!.action).toBeUndefined();
+  });
+});

components/mail/__tests__/mail-app-source-routing.test.tsx

@@ -185,7 +185,7 @@ describe('the open message of a group account in a tag view', () => {
     render(<MailApp />);
     fireEvent.click(await screen.findByText('stub archive', {}, { timeout: 5000 }));
     await waitFor(() => expect(moveThreadToMailbox).toHaveBeenCalled());
-    expect(moveThreadToMailbox).toHaveBeenCalledWith(client, 'eaaaaab', 'ce:k', 'login-a/ce:eaaaaab');
+    expect(moveThreadToMailbox).toHaveBeenCalledWith(client, 'eaaaaab', 'ce:k', 'login-a/ce:eaaaaab', expect.any(Function));
   });
 
   it('is deleted into the group\'s Deleted Items, not the own one', async () => {
@@ -215,7 +215,7 @@ describe('archiving a group message by month', () => {
     fireEvent.click(await screen.findByText('stub archive', {}, { timeout: 5000 }));
     await waitFor(() => expect(moveThreadToMailbox).toHaveBeenCalled());
     expect(client.createMailbox).not.toHaveBeenCalled();
-    expect(moveThreadToMailbox).toHaveBeenCalledWith(client, 'eaaaaab', 'ce:m1', 'login-a/ce:eaaaaab');
+    expect(moveThreadToMailbox).toHaveBeenCalledWith(client, 'eaaaaab', 'ce:m1', 'login-a/ce:eaaaaab', expect.any(Function));
   });
 
   it('reuses them with the group\'s Inbox open', async () => {
@@ -225,7 +225,7 @@ describe('archiving a group message by month', () => {
     fireEvent.click(await screen.findByText('stub archive', {}, { timeout: 5000 }));
     await waitFor(() => expect(moveThreadToMailbox).toHaveBeenCalled());
     expect(client.createMailbox).not.toHaveBeenCalled();
-    expect(moveThreadToMailbox).toHaveBeenCalledWith(client, 'eaaaaab', 'ce:m1', 'eaaaaab');
+    expect(moveThreadToMailbox).toHaveBeenCalledWith(client, 'eaaaaab', 'ce:m1', 'eaaaaab', expect.any(Function));
   });
 
   // The own account has a folder with the server id of the group's Archive,
@@ -242,7 +242,7 @@ describe('archiving a group message by month', () => {
     render(<MailApp />);
     fireEvent.click(await screen.findByText('stub archive', {}, { timeout: 5000 }));
     await waitFor(() => expect(moveThreadToMailbox).toHaveBeenCalled());
-    expect(moveThreadToMailbox).toHaveBeenCalledWith(client, 'eaaaaab', 'ce:m1', 'eaaaaab');
+    expect(moveThreadToMailbox).toHaveBeenCalledWith(client, 'eaaaaab', 'ce:m1', 'eaaaaab', expect.any(Function));
   });
 
   it('creates a missing year folder in the group account with the group\'s Inbox open', async () => {

components/mail/mail-app.tsx

@@ -37,7 +37,7 @@ import type { UnifiedAccountClient } from "@/lib/unified-mailbox";
 import { connectedAccountsGrew } from "@/lib/unified-mailbox";
 import { messagePriorityFromHeaders, type MessagePriority } from "@/lib/message-priority";
 import { KeyboardShortcutsModal } from "@/components/keyboard-shortcuts-modal";
-import { useEmailStore, pendingInitialData, buildUnifiedAccountClients, invalidateUnifiedMailboxes, captureViewToken, ArchiveMailboxNotFoundError, ensureArchiveMailbox, resolveSelectedEmails, resolveUnstampedEmailAccountId, resolveEmailBlobContext, resolveEmailActionContext, emailWriteSource, emailLinkSource, type EmailBlobContext, emptyFolderMovesToTrash, bulkDeleteIsPermanent, shouldConfirmBulkDelete, isAggregateListView, removalFolder, canRemoveFromFolder } from "@/stores/email-store";
+import { useEmailStore, pendingInitialData, buildUnifiedAccountClients, invalidateUnifiedMailboxes, captureViewToken, ArchiveMailboxNotFoundError, ensureArchiveMailbox, resolveSelectedEmails, resolveUnstampedEmailAccountId, resolveEmailBlobContext, resolveEmailActionContext, emailWriteSource, emailLinkSource, type EmailBlobContext, emptyFolderMovesToTrash, bulkDeleteIsPermanent, shouldConfirmBulkDelete, isAggregateListView, removalFolder, canRemoveFromFolder, restoreBatchesFor, restoreBatchesForSelection, type EmailRestoreBatch } from "@/stores/email-store";
 import { findDraftIdentityIdForLogin, listRowSource, resolveDraftSource, type DraftSource } from "@/lib/draft-source";
 import { useRemoveFromFolder } from "@/hooks/use-remove-from-folder";
 import { groupSearchScopeFolders, SEARCH_SCOPE_ALL_FOLDERS } from "@/lib/search-scope-folders";
@@ -46,7 +46,7 @@ import { cancelFailureToast, partlyRefusedWarning, rescheduleFailureToast } from
 import { formatRejectedRecipients, RescheduleRestoredError } from "@/lib/jmap/client";
 import { subscribePushStateChanges } from "@/lib/push-events";
 import { createMailPushListener } from "@/lib/mail-push-listener";
-import { runBatchEmailAction } from "@/lib/email-action-toast";
+import { runBatchEmailAction, toastWithUndo, undoLabels, undoMoveAction } from "@/lib/email-action-toast";
 import { MailboxShareDialog } from "@/components/layout/mailbox-share-dialog";
 import { ShareNotificationToaster } from "@/components/layout/share-notification-toaster";
 import { CalendarEventNotificationToaster } from "@/components/layout/calendar-event-notification-toaster";
@@ -214,6 +214,9 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
   // Static Lite build: the route params are empty, read the link from the URL.
   const linkSegments = useLiteLinkSegments('mail', routeSegments);
   const t = useTranslations();
+  const tNotifications = useTranslations('notifications');
+  // The toasts' Undo after a delete to Trash, archive, move or spam report.
+  const undo = undoLabels(tNotifications);
   const tCommon = useTranslations('common');
   const appName = productName(useConfig().appName);
   const tQuote = useTranslations('quote_header');
@@ -936,8 +939,10 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
       if (isScheduledView) return;
       if (shortcutsTargetSelection && client) {
         const count = selectedEmailKeys.size;
+        const restore = restoreBatchesForSelection(client);
         await runBatchEmailAction(() => batchArchive(client), {
           success: t('notifications.emails_archived', { count }),
+          undo: undoMoveAction(client, restore, undo),
           error: t('notifications.error_archiving'),
           describeError: (error) => error instanceof ArchiveMailboxNotFoundError
             ? t('email_viewer.archive_mailbox_not_found')
@@ -968,9 +973,11 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
           if (!confirmed) return;
         }
         const count = selectedEmailKeys.size;
+        const restore = permanent ? null : restoreBatchesForSelection(client);
         await runBatchEmailAction(() => batchDelete(client, permanent), {
           success: t('notifications.emails_deleted', { count }),
           error: t('notifications.error_deleting'),
+          undo: undoMoveAction(client, restore, undo),
         });
       } else if (selectedEmail) {
         handleDelete();
@@ -1009,11 +1016,12 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
         // The spam actions take bare ids of the viewed account: resolve the
         // selection keys through the loaded rows and thread members.
         const ids = resolveSelectedEmails(useEmailStore.getState()).map(e => e.id);
+        const restore = restoreBatchesForSelection(client);
         try {
           if (isInJunk) {
-            if (await batchUndoSpam(client, ids)) toast.success(t('email_viewer.spam.toast_not_spam_batch', { count: ids.length }));
+            if (await batchUndoSpam(client, ids)) toastWithUndo(t('email_viewer.spam.toast_not_spam_batch', { count: ids.length }), undoMoveAction(client, restore, undo));
           } else {
-            if (await batchMarkAsSpam(client, ids)) toast.success(t('email_viewer.spam.toast_batch', { count: ids.length }));
+            if (await batchMarkAsSpam(client, ids)) toastWithUndo(t('email_viewer.spam.toast_batch', { count: ids.length }), undoMoveAction(client, restore, undo));
           }
         } catch (error) {
           console.error("Failed to batch toggle spam:", error);
@@ -2809,7 +2817,9 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
     const isInTrash = currentMailbox?.role === 'trash';
     // Trash, Junk with "permanently delete junk", or the "Delete permanently"
     // setting: the mail is destroyed, so ask first, as the batch delete does.
+    // A move to Trash gets Undo instead.
     const permanent = bulkDeleteIsPermanent(currentMailbox);
+    const restore = permanent ? null : restoreBatchesFor([emailToDelete], client);
 
     if (permanent) {
       const confirmed = await confirmDialog({
@@ -2826,7 +2836,9 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
     // it. In Trash it always destroys. (#281 for the account routing)
     try {
       // false: a plugin stopped it and said why, so no "deleted" here.
-      if (await deleteEmail(client, emailToDelete.id, isInTrash, emailKeyFor(emailToDelete))) toast.success(t('notifications.email_deleted'));
+      if (await deleteEmail(client, emailToDelete.id, isInTrash, emailKeyFor(emailToDelete))) {
+        toastWithUndo(t('notifications.email_deleted'), undoMoveAction(client, restore, undo));
+      }
     } catch (error) {
       console.error("Failed to delete email:", error);
       toast.error(t('notifications.error_deleting'), error instanceof Error ? error.message : undefined);
@@ -2880,8 +2892,10 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
       if (!archiveMailbox) return; // a plugin refused the Archive folder
 
       let archived: boolean;
+      let restore: EmailRestoreBatch[] | null = null;
+      const keepRestore = (batches: EmailRestoreBatch[]) => { restore = batches; };
       if (archiveMode === 'single') {
-        archived = await moveThreadToMailbox(client, emailToArchive.id, archiveMailbox.id, emailKeyFor(emailToArchive));
+        archived = await moveThreadToMailbox(client, emailToArchive.id, archiveMailbox.id, emailKeyFor(emailToArchive), keepRestore);
       } else {
         const emailDate = new Date(emailToArchive.receivedAt);
         const year = emailDate.getFullYear().toString();
@@ -2906,7 +2920,7 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
         }
 
         if (archiveMode === 'year') {
-          archived = await moveThreadToMailbox(client, emailToArchive.id, yearMailbox.id, emailKeyFor(emailToArchive));
+          archived = await moveThreadToMailbox(client, emailToArchive.id, yearMailbox.id, emailKeyFor(emailToArchive), keepRestore);
         } else {
           const yearId = yearMailbox.originalId || yearMailbox.id;
           const afterYear = readMailboxes();
@@ -2916,7 +2930,7 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
             if (!monthMailbox) return; // a plugin refused the folder
             await refreshMailboxes();
           }
-          archived = await moveThreadToMailbox(client, emailToArchive.id, monthMailbox.id, emailKeyFor(emailToArchive));
+          archived = await moveThreadToMailbox(client, emailToArchive.id, monthMailbox.id, emailKeyFor(emailToArchive), keepRestore);
         }
       }
       if (!archived) return;
@@ -2928,7 +2942,7 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
         setConversationEmails([]);
       }
 
-      toast.success(t('notifications.email_archived'));
+      toastWithUndo(t('notifications.email_archived'), undoMoveAction(client, restore, undo));
       void refreshMailboxes();
     } catch (error) {
       console.error("Failed to archive email:", error);
@@ -2951,10 +2965,18 @@ export function MailApp({ linkSegments: routeSegments }: MailAppProps = {}) {
     const destinationList = [mailboxes, ...Object.values(accountMailboxes)]
       .find(list => list.some(m => m.id === mailboxId));
     const destination = destinationList?.find(m => m.id === mailboxId);
+    // Undo for a move within the message's own account; a move to another
+    // account copies the message there, which Undo can't take back.
+    const email = useEmailStore.getState().emails.find(e => (emailKey ? emailKeyFor(e) === emailKey : e.id === emailId));
+    const sourceFolder = [mailboxes, ...Object.values(accountMailboxes)].flat().find(m => m.id === selectedMailbox);
+    const sourceAccount = email?.sourceAccountId ?? sourceFolder?.accountId;
+    const crossAccount = !!destination?.accountId && !!sourceAccount && destination.accountId !== sourceAccount;
+    const restore = email && !crossAccount ? restoreBatchesFor([email], client) : null;
     try {
       if (!(await moveToMailboxCrossAware(client, emailId, mailboxId, emailKey))) return;
-      toast.success(
+      toastWithUndo(
         t('notifications.email_moved'),
+        undoMoveAction(client, restore, undo),
         destination && destinationList
           ? t('notifications.moved_to_mailbox', { mailbox: getMailboxPath(destination, destinationList) })
           : undefined,

hooks/use-mailbox-drop.ts

@@ -2,7 +2,7 @@
 
 import { useCallback, useState, DragEvent } from "react";
 import { Mailbox, Email } from "@/lib/jmap/types";
-import { useEmailStore, isAggregateListView } from "@/stores/email-store";
+import { useEmailStore, isAggregateListView, restoreBatchesFor, type EmailRestoreBatch } from "@/stores/email-store";
 import { useShallow } from "zustand/react/shallow";
 import { emailKeyFor } from "@/lib/thread-utils";
 import { useAuthStore } from "@/stores/auth-store";
@@ -35,8 +35,10 @@ interface UseMailboxDropOptions {
    */
   accountId?: string;
   onDropComplete?: () => void;
-  // Translation callbacks for toast messages
-  onSuccess?: (count: number, mailboxName: string) => void;
+  // Translation callbacks for toast messages. `restore` says where the
+  // messages were, for the toast's Undo; null when the move went to another
+  // account, which Undo can't take back.
+  onSuccess?: (count: number, mailboxName: string, restore: EmailRestoreBatch[] | null) => void;
   onError?: (error: string) => void;
 }
 
@@ -132,7 +134,12 @@ export function useMailboxDrop({ mailbox, accountId, onDropComplete, onSuccess,
 
       let isCrossAccount = false;
       let moved: boolean;
+      let restore: EmailRestoreBatch[] | null = null;
       if (isAggregateListView()) {
+        // Undo only when every row moved inside its own account.
+        const inPlace = draggedEmails.length > 0 && draggedEmails.every(em =>
+          em.sourceAccountId === mailbox.accountId && (!em.sourceClientAccountId || em.sourceClientAccountId === destAccountId));
+        if (inPlace) restore = restoreBatchesFor(draggedEmails, client);
         // A list that mixes accounts (unified, tag and "All folders" views)
         // stamps every row with its login and account. The store moves each
         // of those groups apart - in place only in the folder's own account,
@@ -190,6 +197,7 @@ export function useMailboxDrop({ mailbox, accountId, onDropComplete, onSuccess,
           moved = await crossAccountMoveEmails(bySource, destAccountId, jmapDestId, destJmapOverride, sourceJmapOverride);
         } else {
           // Single-account or same-account-shared move: bulk JMAP request.
+          restore = restoreBatchesFor(draggedEmails.filter(em => emailIds.includes(em.id)), client);
           moved = await moveEmailsToMailbox(client, emailIds, mailbox.id);
         }
       }
@@ -218,7 +226,7 @@ export function useMailboxDrop({ mailbox, accountId, onDropComplete, onSuccess,
       const mailboxPath = getMailboxPath(mailbox, mailboxes);
 
       if (onSuccess) {
-        onSuccess(emailIds.length, mailboxPath);
+        onSuccess(emailIds.length, mailboxPath, restore);
       } else {
         if (emailIds.length === 1) {
           toast.success("Email moved", `Moved to ${mailboxPath}`);

hooks/use-remove-from-folder.ts

@@ -3,14 +3,14 @@
 import { useCallback } from "react";
 import { useTranslations } from "next-intl";
 import { useAuthStore } from "@/stores/auth-store";
-import { useEmailStore, removalFolder } from "@/stores/email-store";
-import { runBatchEmailAction } from "@/lib/email-action-toast";
+import { useEmailStore, removalFolder, restoreBatchesFor } from "@/stores/email-store";
+import { runBatchEmailAction, undoLabels, undoMoveAction } from "@/lib/email-action-toast";
 import { localizeMailboxName } from "@/lib/mailbox-label";
 import type { Email } from "@/lib/jmap/types";
 
 /**
  * "Remove from this folder" (#615): takes the messages out of the open folder
- * only, keeps them in their other folders, and toasts the outcome.
+ * only, keeps them in their other folders, and toasts the outcome with Undo.
  */
 export function useRemoveFromFolder(): (emails: Email[]) => Promise<void> {
   const t = useTranslations("notifications");
@@ -24,9 +24,11 @@ export function useRemoveFromFolder(): (emails: Email[]) => Promise<void> {
     const mailbox = folder
       ? localizeMailboxName(folder.role, folder.name, (key) => tSidebar(`mailboxes.${key}`))
       : "";
+    const restore = restoreBatchesFor(emails, client);
     await runBatchEmailAction(() => removeFromMailbox(client, emails), {
       success: t("removed_from_folder", { mailbox }),
       error: t("remove_from_folder_failed"),
+      undo: undoMoveAction(client, restore, undoLabels(t)),
     });
   }, [client, removeFromMailbox, t, tSidebar]);
 }

lib/demo/demo-client.ts

@@ -652,6 +652,19 @@ export class DemoJMAPClient implements IJMAPClient {
     this.recalcMailboxCounts();
   }
 
+  async restoreEmails(emails: Array<{ id: string; mailboxIds: Record<string, boolean>; seen?: boolean }>): Promise<void> {
+    for (const { id, mailboxIds, seen } of emails) {
+      const email = this.data.emails.find(e => e.id === id);
+      if (!email) continue;
+      email.mailboxIds = { ...mailboxIds };
+      if (seen !== undefined) {
+        if (seen) email.keywords.$seen = true;
+        else delete email.keywords.$seen;
+      }
+    }
+    this.recalcMailboxCounts();
+  }
+
   async emptyMailbox(mailboxId: string, _accountId?: string): Promise<number> {
     const before = this.data.emails.length;
     this.data.emails = this.data.emails.filter(e => !e.mailboxIds[mailboxId]);

lib/email-action-toast.ts

@@ -1,5 +1,58 @@
 import { toast } from "@/stores/toast-store";
-import { useEmailStore } from "@/stores/email-store";
+import { useEmailStore, type EmailRestoreBatch } from "@/stores/email-store";
+import type { ToastAction } from "@/components/ui/toast";
+import type { IJMAPClient } from "@/lib/jmap/client-interface";
+
+/** How long a toast with Undo stays, so there is time to reach the button. */
+export const UNDO_TOAST_DURATION = 8000;
+
+/** The words the Undo action needs, from the `notifications` namespace. */
+export interface UndoLabels {
+  undo: string;
+  done: string;
+  failed: string;
+}
+
+/** `t` of the `notifications` namespace → UndoLabels. */
+export function undoLabels(t: (key: string) => string): UndoLabels {
+  return { undo: t("undo"), done: t("undo_done"), failed: t("undo_failed") };
+}
+
+/**
+ * The toast's Undo for a reversible move (delete to Trash, archive, move,
+ * report spam, remove from folder): puts the messages back where `batches`
+ * says they were. None when there is nothing to put back.
+ */
+export function undoMoveAction(
+  client: IJMAPClient | null | undefined,
+  batches: EmailRestoreBatch[] | null | undefined,
+  labels: UndoLabels,
+): ToastAction | undefined {
+  if (!client || !batches || !batches.some(b => b.points.length > 0)) return undefined;
+  return {
+    label: labels.undo,
+    onClick: () => {
+      void (async () => {
+        try {
+          await useEmailStore.getState().restoreEmails(client, batches);
+          toast.success(labels.done);
+        } catch (error) {
+          console.error("Failed to undo:", error);
+          toast.error(labels.failed);
+        }
+      })();
+    },
+  };
+}
+
+/** A success toast, with Undo when the action can be undone. */
+export function toastWithUndo(title: string, undo: ToastAction | undefined, message?: string): void {
+  if (!undo) {
+    toast.success(title, message);
+    return;
+  }
+  toast.success(title, { message, action: undo, duration: UNDO_TOAST_DURATION });
+}
 
 /**
  * Runs a bulk email-store action and toasts the outcome: a failure always, a
@@ -7,11 +60,13 @@ import { useEmailStore } from "@/stores/email-store";
  * through `state.error` instead of throwing (batchArchive does both), so a
  * resolved promise alone does not mean the mail moved. An action that
  * resolves `false` did nothing: a plugin vetoed it (and told the user why) or
- * there was nothing to act on, so there is no success to report.
+ * there was nothing to act on, so there is no success to report. `undo` goes
+ * on the success toast only: after a partial failure the list is reloaded and
+ * the error says what stayed.
  */
 export async function runBatchEmailAction(
   run: () => Promise<boolean | void>,
-  messages: { success?: string; error: string; describeError?: (error: unknown) => string | undefined },
+  messages: { success?: string; error: string; describeError?: (error: unknown) => string | undefined; undo?: ToastAction },
 ): Promise<void> {
   // An error left over from an earlier action is not this action's outcome.
   useEmailStore.setState({ error: null });
@@ -28,6 +83,6 @@ export async function runBatchEmailAction(
   if (storeError) {
     toast.error(messages.error, storeError);
   } else if (ran !== false && messages.success) {
-    toast.success(messages.success);
+    toastWithUndo(messages.success, messages.undo);
   }
 }

lib/jmap/client-interface.ts

@@ -360,6 +360,12 @@ export interface IJMAPClient {
    * least one mailbox, so the server refuses this for a message only in it.
    */
   removeEmailsFromMailbox(emailIds: string[], mailboxId: string, accountId?: string): Promise<void>;
+  /**
+   * Put messages back where they were before a move, delete to Trash,
+   * archive or "remove from folder": each one's whole `mailboxIds`, and its
+   * read state when `seen` is given. Backs the toasts' Undo.
+   */
+  restoreEmails(emails: Array<{ id: string; mailboxIds: Record<string, boolean>; seen?: boolean }>, accountId?: string): Promise<void>;
   emptyMailbox(mailboxId: string, accountId?: string): Promise<number>;
   moveMailboxContents(fromMailboxId: string, toMailboxId: string, accountId?: string, markAsRead?: boolean): Promise<number>;
   markMailboxAsRead(mailboxId: string, accountId?: string): Promise<number>;

lib/jmap/client.ts

@@ -3600,6 +3600,20 @@ export class JMAPClient implements IJMAPClient {
     }
   }
 
+  async restoreEmails(emails: Array<{ id: string; mailboxIds: Record<string, boolean>; seen?: boolean }>, accountId?: string): Promise<void> {
+    if (emails.length === 0) return;
+    for (const batch of batched(emails, this.getMaxObjectsInSet())) {
+      const update = Object.fromEntries(batch.map(email => [email.id, {
+        mailboxIds: email.mailboxIds,
+        ...(email.seen === undefined ? {} : { 'keywords/$seen': email.seen ? true : null }),
+      }]));
+      const response = await this.request([
+        ["Email/set", { accountId: accountId || this.accountId, update }, "0"],
+      ]);
+      assertSetSucceeded(response, 'Failed to restore emails');
+    }
+  }
+
   async emptyMailbox(mailboxId: string, accountId?: string): Promise<number> {
     const targetAccountId = accountId || this.accountId;
     const batchSize = Math.min(500, this.getMaxObjectsInSet());

locales/ar/common.json

@@ -940,6 +940,9 @@
     "move_failed": "فشل النقل",
     "removed_from_folder": "تمت الإزالة من {mailbox}",
     "remove_from_folder_failed": "تعذرت الإزالة من هذا المجلد",
+    "undo": "تراجع",
+    "undo_done": "تمت الإعادة إلى مكانها",
+    "undo_failed": "تعذّر التراجع",
     "emails_copied": "تم نسخ {count} رسالة",
     "copy_failed": "فشل النسخ",
     "move_error": "تعذّر نقل الرسائل إلى المجلد المحدد",

locales/ca/common.json

@@ -940,6 +940,9 @@
     "move_failed": "No s'ha pogut moure",
     "removed_from_folder": "S'ha tret de {mailbox}",
     "remove_from_folder_failed": "No s'ha pogut treure d'aquesta carpeta",
+    "undo": "Desfés",
+    "undo_done": "S'ha tornat al lloc",
+    "undo_failed": "No s'ha pogut desfer",
     "emails_copied": "{count} correus copiats",
     "copy_failed": "No s'ha pogut copiar",
     "move_error": "No s'han pogut moure els correus a la carpeta seleccionada",

locales/cs/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Přesun selhal",
     "removed_from_folder": "Odebráno ze složky {mailbox}",
     "remove_from_folder_failed": "Odebrání z této složky se nezdařilo",
+    "undo": "Zpět",
+    "undo_done": "Vráceno zpět",
+    "undo_failed": "Nepodařilo se vrátit zpět",
     "emails_copied": "{count} zpráv bylo zkopírováno",
     "copy_failed": "Kopírování selhalo",
     "move_error": "Zprávu nelze přesunout do vybrané složky",

locales/da/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Flytning mislykkedes",
     "removed_from_folder": "Fjernet fra {mailbox}",
     "remove_from_folder_failed": "Kunne ikke fjerne fra denne mappe",
+    "undo": "Fortryd",
+    "undo_done": "Flyttet tilbage",
+    "undo_failed": "Kunne ikke fortrydes",
     "emails_copied": "{count} e-mails kopieret",
     "copy_failed": "Kopiering mislykkedes",
     "move_error": "Kunne ikke flytte e-mails til den valgte mappe",

locales/de/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Verschieben fehlgeschlagen",
     "removed_from_folder": "Aus {mailbox} entfernt",
     "remove_from_folder_failed": "Konnte nicht aus diesem Ordner entfernt werden",
+    "undo": "Rückgängig",
+    "undo_done": "Zurückverschoben",
+    "undo_failed": "Konnte nicht rückgängig gemacht werden",
     "emails_copied": "{count} E-Mails kopiert",
     "copy_failed": "Kopieren fehlgeschlagen",
     "move_error": "E-Mails konnten nicht in den ausgewählten Ordner verschoben werden",

locales/en/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Move failed",
     "removed_from_folder": "Removed from {mailbox}",
     "remove_from_folder_failed": "Could not remove from this folder",
+    "undo": "Undo",
+    "undo_done": "Moved back",
+    "undo_failed": "Couldn't undo",
     "emails_copied": "{count} emails copied",
     "copy_failed": "Copy failed",
     "move_error": "Could not move emails to the selected folder",

locales/es/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Error al mover",
     "removed_from_folder": "Quitado de {mailbox}",
     "remove_from_folder_failed": "No se pudo quitar de esta carpeta",
+    "undo": "Deshacer",
+    "undo_done": "Devuelto a su sitio",
+    "undo_failed": "No se pudo deshacer",
     "emails_copied": "{count} correos copiados",
     "copy_failed": "Error al copiar",
     "move_error": "No se pudieron mover los correos a la carpeta seleccionada",

locales/et/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Liigutamine ebaõnnestus",
     "removed_from_folder": "Eemaldatud kaustast {mailbox}",
     "remove_from_folder_failed": "Sellest kaustast ei õnnestunud eemaldada",
+    "undo": "Võta tagasi",
+    "undo_done": "Tõstetud tagasi",
+    "undo_failed": "Tagasivõtmine ei õnnestunud",
     "emails_copied": "{count} kirja kopeeritud",
     "copy_failed": "Kopeerimine ebaõnnestus",
     "move_error": "E-kirju ei õnnestunud valitud kausta liigutada",

locales/fa/common.json

@@ -940,6 +940,9 @@
     "move_failed": "انتقال ناموفق بود",
     "removed_from_folder": "از {mailbox} حذف شد",
     "remove_from_folder_failed": "حذف از این پوشه انجام نشد",
+    "undo": "بازگردانی",
+    "undo_done": "به جای قبلی برگردانده شد",
+    "undo_failed": "بازگردانی ممکن نشد",
     "emails_copied": "{count} ایمیل کپی شد",
     "copy_failed": "کپی ناموفق بود",
     "move_error": "انتقال ایمیل‌ها به پوشه انتخاب شده ممکن نیست",

locales/fr/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Échec du déplacement",
     "removed_from_folder": "Retiré de {mailbox}",
     "remove_from_folder_failed": "Impossible de retirer de ce dossier",
+    "undo": "Annuler",
+    "undo_done": "Remis à sa place",
+    "undo_failed": "Impossible d'annuler",
     "emails_copied": "{count} emails copiés",
     "copy_failed": "Échec de la copie",
     "move_error": "Impossible de déplacer les emails vers le dossier sélectionné",

locales/he/common.json

@@ -905,6 +905,9 @@
     "move_failed": "המהלך נכשל",
     "removed_from_folder": "הוסר מ-{mailbox}",
     "remove_from_folder_failed": "לא ניתן להסיר מתיקייה זו",
+    "undo": "בטל",
+    "undo_done": "הוחזר למקומו",
+    "undo_failed": "לא ניתן היה לבטל",
     "emails_copied": "{count} הודעות הועתקו",
     "copy_failed": "ההעתקה נכשלה",
     "move_error": "לא ניתן היה להעביר הודעות דוא\"ל לתיקיה שנבחרה",

locales/hu/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Áthelyezés sikertelen",
     "removed_from_folder": "Eltávolítva innen: {mailbox}",
     "remove_from_folder_failed": "Nem sikerült eltávolítani ebből a mappából",
+    "undo": "Visszavonás",
+    "undo_done": "Visszahelyezve",
+    "undo_failed": "Nem sikerült visszavonni",
     "emails_copied": "{count} e-mail másolva",
     "copy_failed": "Másolás sikertelen",
     "move_error": "Nem sikerült áthelyezni az e-maileket a kiválasztott mappába",

locales/it/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Spostamento non riuscito",
     "removed_from_folder": "Rimosso da {mailbox}",
     "remove_from_folder_failed": "Impossibile rimuovere da questa cartella",
+    "undo": "Annulla",
+    "undo_done": "Rimesso al suo posto",
+    "undo_failed": "Impossibile annullare",
     "emails_copied": "{count} messaggi copiati",
     "copy_failed": "Copia non riuscita",
     "move_error": "Impossibile spostare i messaggi nella cartella selezionata",

locales/ja/common.json

@@ -940,6 +940,9 @@
     "move_failed": "移動に失敗しました",
     "removed_from_folder": "{mailbox} から削除しました",
     "remove_from_folder_failed": "このフォルダから削除できませんでした",
+    "undo": "元に戻す",
+    "undo_done": "元の場所に戻しました",
+    "undo_failed": "元に戻せませんでした",
     "emails_copied": "{count}件のメールをコピーしました",
     "copy_failed": "コピーに失敗しました",
     "move_error": "選択したフォルダにメールを移動できませんでした",

locales/ko/common.json

@@ -940,6 +940,9 @@
     "move_failed": "이동에 실패했어요",
     "removed_from_folder": "{mailbox}에서 제거됨",
     "remove_from_folder_failed": "이 폴더에서 제거하지 못했습니다",
+    "undo": "실행 취소",
+    "undo_done": "원래 위치로 되돌렸어요",
+    "undo_failed": "실행 취소하지 못했어요",
     "emails_copied": "{count}개의 메일이 복사되었어요",
     "copy_failed": "복사에 실패했어요",
     "move_error": "선택한 폴더로 메일을 이동할 수 없어요",

locales/lv/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Pārvietošanas kļūda",
     "removed_from_folder": "Noņemts no {mailbox}",
     "remove_from_folder_failed": "Neizdevās noņemt no šīs mapes",
+    "undo": "Atsaukt",
+    "undo_done": "Pārvietots atpakaļ",
+    "undo_failed": "Neizdevās atsaukt",
     "emails_copied": "{count} vēstules nokopētas",
     "copy_failed": "Kopēšanas kļūda",
     "move_error": "Neizdevās pārvietot vēstules uz izvēlēto mapi",

locales/mn/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Зөөж чадсангүй",
     "removed_from_folder": "{mailbox}-с хасагдлаа",
     "remove_from_folder_failed": "Энэ хавтаснаас хасаж чадсангүй",
+    "undo": "Буцаах",
+    "undo_done": "Буцааж шилжүүллээ",
+    "undo_failed": "Буцааж чадсангүй",
     "emails_copied": "{count} имэйлийг хуулсан",
     "copy_failed": "Хуулж чадсангүй",
     "move_error": "Имэйлүүдийг сонгосон хавтас руу зөөж чадсангүй",

locales/nb/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Kunne ikke flytte e-posten",
     "removed_from_folder": "Fjernet fra {mailbox}",
     "remove_from_folder_failed": "Kunne ikke fjerne fra denne mappen",
+    "undo": "Angre",
+    "undo_done": "Flyttet tilbake",
+    "undo_failed": "Kunne ikke angre",
     "emails_copied": "{count} e-poster er kopiert",
     "copy_failed": "Kunne ikke kopiere",
     "move_error": "Kunne ikke flytte e-poster til den valgte mappen",

locales/nl/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Verplaatsen mislukt",
     "removed_from_folder": "Verwijderd uit {mailbox}",
     "remove_from_folder_failed": "Kon niet uit deze map verwijderen",
+    "undo": "Ongedaan maken",
+    "undo_done": "Teruggezet",
+    "undo_failed": "Kon niet ongedaan worden gemaakt",
     "emails_copied": "{count} e-mails gekopieerd",
     "copy_failed": "Kopiëren mislukt",
     "move_error": "Kan e-mails niet verplaatsen naar de geselecteerde map",

locales/pl/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Przenoszenie nie powiodło się",
     "removed_from_folder": "Usunięto z folderu {mailbox}",
     "remove_from_folder_failed": "Nie udało się usunąć z tego folderu",
+    "undo": "Cofnij",
+    "undo_done": "Przeniesiono z powrotem",
+    "undo_failed": "Nie udało się cofnąć",
     "emails_copied": "{count} wiadomości skopiowanych",
     "copy_failed": "Kopiowanie nie powiodło się",
     "move_error": "Nie można przenieść wiadomości do wybranego folderu",

locales/pt/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Falha ao mover",
     "removed_from_folder": "Removido de {mailbox}",
     "remove_from_folder_failed": "Não foi possível remover desta pasta",
+    "undo": "Desfazer",
+    "undo_done": "Devolvido ao lugar",
+    "undo_failed": "Não foi possível desfazer",
     "emails_copied": "{count} e-mails copiados",
     "copy_failed": "Falha ao copiar",
     "move_error": "Não foi possível mover os e-mails para a pasta selecionada",

locales/ro/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Mutarea a eșuat",
     "removed_from_folder": "Eliminat din {mailbox}",
     "remove_from_folder_failed": "Nu s-a putut elimina din acest dosar",
+    "undo": "Anulează",
+    "undo_done": "Mutat înapoi",
+    "undo_failed": "Nu s-a putut anula",
     "emails_copied": "{count} e-mailuri copiate",
     "copy_failed": "Copierea a eșuat",
     "move_error": "Nu s-au putut muta e-mailurile în folderul selectat",

locales/ru/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Ошибка перемещения",
     "removed_from_folder": "Убрано из папки {mailbox}",
     "remove_from_folder_failed": "Не удалось убрать из этой папки",
+    "undo": "Отменить",
+    "undo_done": "Возвращено на место",
+    "undo_failed": "Не удалось отменить",
     "emails_copied": "{count} писем скопировано",
     "copy_failed": "Ошибка копирования",
     "move_error": "Не удалось переместить письма в выбранную папку",

locales/sk/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Presun zlyhal",
     "removed_from_folder": "Odstránené z priečinka {mailbox}",
     "remove_from_folder_failed": "Odstránenie z tohto priečinka zlyhalo",
+    "undo": "Späť",
+    "undo_done": "Presunuté späť",
+    "undo_failed": "Nepodarilo sa vrátiť späť",
     "emails_copied": "{count} e-mailov bolo skopírovaných",
     "copy_failed": "Kopírovanie zlyhalo",
     "move_error": "E-maily sa nedá presunúť do vybratej priečinky",

locales/th/common.json

@@ -382,6 +382,9 @@
     "move_failed": "ย้ายไม่สำเร็จ",
     "removed_from_folder": "นำออกจาก {mailbox} แล้ว",
     "remove_from_folder_failed": "ไม่สามารถนำออกจากโฟลเดอร์นี้ได้",
+    "undo": "เลิกทำ",
+    "undo_done": "ย้ายกลับแล้ว",
+    "undo_failed": "ไม่สามารถเลิกทำได้",
     "emails_copied": "{count} อีเมลถูกคัดลอกแล้ว",
     "copy_failed": "คัดลอกไม่สำเร็จ",
     "move_error": "ไม่สามารถย้ายอีเมลไปยังโฟลเดอร์ที่เลือกได้",

locales/tr/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Taşıma başarısız",
     "removed_from_folder": "{mailbox} klasöründen kaldırıldı",
     "remove_from_folder_failed": "Bu klasörden kaldırılamadı",
+    "undo": "Geri al",
+    "undo_done": "Geri taşındı",
+    "undo_failed": "Geri alınamadı",
     "emails_copied": "{count} e-posta kopyalandı",
     "copy_failed": "Kopyalama başarısız",
     "move_error": "E-postalar seçilen klasöre taşınamadı",

locales/uk/common.json

@@ -940,6 +940,9 @@
     "move_failed": "Не вдалося перемістити",
     "removed_from_folder": "Прибрано з папки {mailbox}",
     "remove_from_folder_failed": "Не вдалося прибрати з цієї папки",
+    "undo": "Скасувати",
+    "undo_done": "Повернуто на місце",
+    "undo_failed": "Не вдалося скасувати",
     "emails_copied": "{count} електронних листів скопійовано",
     "copy_failed": "Не вдалося скопіювати",
     "move_error": "Не вдалося перемістити електронні листи до вибраної папки",

locales/zh-TW/common.json

@@ -940,6 +940,9 @@
     "move_failed": "移動郵件失敗",
     "removed_from_folder": "已從 {mailbox} 移除",
     "remove_from_folder_failed": "無法從此資料夾移除",
+    "undo": "復原",
+    "undo_done": "已移回",
+    "undo_failed": "無法復原",
     "emails_copied": "{count} 封郵件已複製",
     "copy_failed": "複製失敗",
     "move_error": "無法將郵件移至選取的信件匣",

locales/zh/common.json

@@ -940,6 +940,9 @@
     "move_failed": "移动失败",
     "removed_from_folder": "已从 {mailbox} 中移除",
     "remove_from_folder_failed": "无法从此文件夹中移除",
+    "undo": "撤销",
+    "undo_done": "已移回",
+    "undo_failed": "无法撤销",
     "emails_copied": "{count} 封邮件已复制",
     "copy_failed": "复制失败",
     "move_error": "无法将邮件移至所选文件夹",

stores/__tests__/email-archive.test.ts

@@ -108,4 +108,32 @@ describe('email-store archive thread behavior', () => {
 
     expect(client.batchMoveEmails).toHaveBeenCalledWith(['email-1', 'email-2'], 'server-archive', 'shared-account');
   });
+
+  it('tells Undo where the archived messages were, and Undo puts them back', async () => {
+    const client = {
+      getThread: vi.fn().mockResolvedValue({ id: 'thread-1', emailIds: ['email-1', 'email-2', 'sent-1'] }),
+      getEmailFields: vi.fn().mockResolvedValue([
+        { id: 'email-1', mailboxIds: { 'server-inbox': true }, keywords: { $seen: true } },
+        { id: 'email-2', mailboxIds: { 'server-inbox': true, 'server-work': true }, keywords: {} },
+        { id: 'sent-1', mailboxIds: { 'server-sent': true }, keywords: { $seen: true } },
+      ]),
+      batchMoveEmails: vi.fn().mockResolvedValue(undefined),
+      restoreEmails: vi.fn().mockResolvedValue(undefined),
+    } as unknown as IJMAPClient;
+    const onMoved = vi.fn();
+    useEmailStore.setState({ refreshCurrentMailbox: vi.fn().mockResolvedValue(undefined), fetchMailboxes: vi.fn().mockResolvedValue(undefined) });
+
+    await useEmailStore.getState().moveThreadToMailbox(client, 'email-1', 'archive-local', undefined, onMoved);
+
+    expect(onMoved).toHaveBeenCalledTimes(1);
+    const [batches] = onMoved.mock.calls[0];
+    expect(batches).toEqual([{ client, accountId: 'shared-account', points: [
+      { id: 'email-1', mailboxIds: { 'server-inbox': true }, seen: true },
+      { id: 'email-2', mailboxIds: { 'server-inbox': true, 'server-work': true }, seen: false },
+    ] }]);
+
+    await useEmailStore.getState().restoreEmails(client, batches);
+    expect(client.restoreEmails).toHaveBeenCalledWith(batches[0].points, 'shared-account');
+    expect(useEmailStore.getState().refreshCurrentMailbox).toHaveBeenCalled();
+  });
 });

stores/email-store.ts

@@ -96,6 +96,59 @@ export function resolveSelectedEmails(state: {
   return [...found.values()];
 }
 
+/** A message's folders and read state before an action moved it. */
+export interface EmailRestorePoint {
+  id: string;
+  /** The server's own folder ids, not the list's `account:id` names. */
+  mailboxIds: Record<string, boolean>;
+  seen: boolean;
+}
+
+/** Restore points of one login and JMAP account, as the action reached them. */
+export interface EmailRestoreBatch {
+  client: IJMAPClient;
+  accountId?: string;
+  points: EmailRestorePoint[];
+}
+
+/**
+ * Where `emails` are now, so the toast's Undo can put them back after a
+ * delete to Trash, an archive, a move or "remove from folder". Taken before
+ * the action, routed the way the action is (resolveEmailActionContext).
+ */
+export function restoreBatchesFor(emails: Email[], client: IJMAPClient): EmailRestoreBatch[] {
+  const batches: EmailRestoreBatch[] = [];
+  for (const email of emails) {
+    if (!email.mailboxIds) continue;
+    let context: ReturnType<typeof resolveEmailActionContext>;
+    try {
+      context = resolveEmailActionContext(email, client);
+    } catch {
+      continue;
+    }
+    const prefix = context.accountId ? `${context.accountId}:` : null;
+    const mailboxIds: Record<string, boolean> = {};
+    for (const [id, inIt] of Object.entries(email.mailboxIds)) {
+      if (inIt) mailboxIds[prefix && id.startsWith(prefix) ? id.slice(prefix.length) : id] = true;
+    }
+    if (Object.keys(mailboxIds).length === 0) continue;
+    let batch = batches.find(b => b.client === context.client && b.accountId === context.accountId);
+    if (!batch) {
+      batch = { client: context.client, accountId: context.accountId, points: [] };
+      batches.push(batch);
+    }
+    if (!batch.points.some(p => p.id === email.id)) {
+      batch.points.push({ id: email.id, mailboxIds, seen: !!email.keywords?.$seen });
+    }
+  }
+  return batches;
+}
+
+/** restoreBatchesFor the selected messages, taken before a batch action. */
+export function restoreBatchesForSelection(client: IJMAPClient): EmailRestoreBatch[] {
+  return restoreBatchesFor(resolveSelectedEmails(useEmailStore.getState()), client);
+}
+
 /** Enough of an email to key a selection by its owning account. */
 type SelectableEmail = Pick<Email, 'id' | 'sourceClientAccountId' | 'sourceAccountId'>;
 
@@ -367,9 +420,11 @@ interface EmailStore {
    * (the open folder, else the one folder the message is in); the others,
    * such as your own message in Sent, stay where they are. `emailKey`
    * (emailKeyFor of the row) picks the right row when the id repeats across
-   * accounts.
+   * accounts. `onMoved` gets where the moved messages were, for Undo.
    */
-  moveThreadToMailbox: (client: IJMAPClient, emailId: string, mailboxId: string, emailKey?: string) => Promise<boolean>;
+  moveThreadToMailbox: (client: IJMAPClient, emailId: string, mailboxId: string, emailKey?: string, onMoved?: (restore: EmailRestoreBatch[]) => void) => Promise<boolean>;
+  /** Undo for a move: put the messages back (restoreBatchesFor) and reload the list and counts. */
+  restoreEmails: (client: IJMAPClient, batches: EmailRestoreBatch[]) => Promise<void>;
   /**
    * Take messages out of the open folder only, leaving them in their other
    * folders (#615). Acts on those of `emails` that removalFolder and
@@ -4844,15 +4899,22 @@ export const useEmailStore = create<EmailStore>((set, get) => ({
     }
   },
 
-  moveThreadToMailbox: async (client, emailId, destinationMailboxId, emailKey): Promise<boolean> => {
+  moveThreadToMailbox: async (client, emailId, destinationMailboxId, emailKey, onMoved): Promise<boolean> => {
     const isTarget = singleEmailMatcher(emailId, emailKey);
     try {
       const state = get();
       const email = state.emails.find(isTarget)
         ?? ((!!state.selectedEmail && isTarget(state.selectedEmail)) ? state.selectedEmail : null);
+      // The one message moves on its own: Undo puts back what the row says.
+      const moveOne = async () => {
+        const restore = email ? restoreBatchesFor([email], client) : [];
+        const moved = await get().moveToMailbox(client, emailId, destinationMailboxId, emailKey);
+        if (moved) onMoved?.(restore);
+        return moved;
+      };
 
       if (!email?.threadId) {
-        return await get().moveToMailbox(client, emailId, destinationMailboxId, emailKey);
+        return await moveOne();
       }
 
       // In unified view route to the email's own account (client + that
@@ -4870,16 +4932,20 @@ export const useEmailStore = create<EmailStore>((set, get) => ({
       const source = sourceId ? mailboxes.find(mb => mb.id === sourceId) : undefined;
       const sourceJmapId = source ? (source.originalId || source.id) : null;
       let threadEmailIds = [emailId];
+      let restorePoints: EmailRestorePoint[] = [];
       if (sourceJmapId && memberIds.length > 1) {
-        const members = await effectiveClient.getEmailFields(memberIds, ['id', 'mailboxIds'], accountId);
-        const inSource = members
-          .filter(m => (m.mailboxIds as Record<string, boolean> | undefined)?.[sourceJmapId])
-          .map(m => m.id as string);
-        threadEmailIds = [...new Set([emailId, ...inSource])];
+        const members = await effectiveClient.getEmailFields(memberIds, ['id', 'mailboxIds', 'keywords'], accountId);
+        const inSource = members.filter(m => (m.mailboxIds as Record<string, boolean> | undefined)?.[sourceJmapId]);
+        threadEmailIds = [...new Set([emailId, ...inSource.map(m => m.id as string)])];
+        restorePoints = inSource.map(m => ({
+          id: m.id as string,
+          mailboxIds: { ...(m.mailboxIds as Record<string, boolean>) },
+          seen: !!(m.keywords as Record<string, boolean> | undefined)?.$seen,
+        }));
       }
 
       if (threadEmailIds.length <= 1) {
-        return await get().moveToMailbox(client, emailId, destinationMailboxId, emailKey);
+        return await moveOne();
       }
 
       const move = { emailIds: threadEmailIds, fromMailboxId: sourceId, toMailboxId: destinationMailboxId };
@@ -4910,6 +4976,11 @@ export const useEmailStore = create<EmailStore>((set, get) => ({
         };
       });
       emitEmailMove(move, mailboxes);
+      if (onMoved) {
+        const picked = restoreBatchesFor([email], client)[0]?.points ?? [];
+        const points = [...restorePoints, ...picked.filter(p => !restorePoints.some(r => r.id === p.id))];
+        onMoved([{ client: effectiveClient, accountId, points }]);
+      }
     } catch (error) {
       set({
         error: error instanceof Error ? error.message : "Failed to move email thread"
@@ -4919,6 +4990,15 @@ export const useEmailStore = create<EmailStore>((set, get) => ({
     return true;
   },
 
+  restoreEmails: async (client, batches): Promise<void> => {
+    for (const batch of batches) {
+      if (batch.points.length > 0) await batch.client.restoreEmails(batch.points, batch.accountId);
+    }
+    // Back in the list the user is looking at, and the folder counts with it.
+    await get().refreshCurrentMailbox(client);
+    void get().fetchMailboxes(client);
+  },
+
   searchEmails: async (client, typedQuery) => {
     const { searchAbortController } = get();